Treated porous material

ABSTRACT

The present disclosure describes a treated cellulosic material comprising: a cellulosic material having a porous structure defining a plurality of pores, at least a portion of the pores containing a treating agent comprising: a polymer comprising an olefin-carboxylic acid copolymer; and a modifying agent comprising a polyamine having greater than or equal to 2 amine groups, wherein the modifying agent crosslinks at least a portion of the polymer.

BACKGROUND OF THE INVENTION

Porous materials, such as cellulosic materials, need to be protectedfrom mold growth, insect attack, rot and water impregnation to helppreserve the physical properties of the cellulosic material. One exampleof such a cellulosic material is wood. A variety of treatment agents andpreservation methods are known to preserve cellulosic materials.

Modern preservation methods typically involve pressure treating thecellulosic material with a treating agent. Pressure treatment typicallyallows the treating agent to penetrate throughout the porous structureof the cellulosic material. The treating agent is typically a chemicalcompound selected to impart the desired physical properties to thecellulosic material. For example, treating agents that increasehardness, add water resistance and improve the dimensional stability ofthe cellulosic material are of interest. Wood is capable of absorbing asmuch as 100% of its weight in water which causes the wood to swell,which after loss of water through evaporation causes the wood to shrink.This process of water absorption/evaporation is non-uniform and createsinternal stresses in the wood leading to splitting, warping, bowing,crooking, twisting, cupping, etc. Also, water can serve as a pathway fororganisms that degrade the cellulosic material, such as insects orfungus. Treating agents that repel insects, or minimize the formation offungi/molds, or improve the overall durability of the cellulosicmaterial are of interest. Further, treating agents can improve windresistance, ultraviolet radiation resistance, stability at high and lowtemperatures, pest resistance, mold resistance, fire resistance andother issues which might affect the physical properties of thecellulosic material.

An improved treating agent for cellulosic materials is desired.

SUMMARY OF THE INVENTION

The present disclosure describes a treated cellulosic materialcomprising: a cellulosic material having a porous structure defining aplurality of pores, at least a portion of the pores containing atreating agent comprising: a polymer comprising an olefin-carboxylicacid copolymer; and a modifying agent comprising a polyamine havinggreater than or equal to 2 amine groups, wherein the modifying agentcrosslinks at least a portion of the polymer.

The present disclosure further describes a method for preparing atreated cellulosic material comprising: (a) providing a cellulosicmaterial; (b) a first treatment protocol comprising impregnating thecellulosic material with an aqueous dispersion comprising a polymer, thepolymer comprising an olefin-carboxylic acid copolymer; and (c) a secondtreatment protocol comprising impregnating the cellulosic material witha modifying agent, the modifying agent comprising a polyamine havinggreater than or equal to 2 amine groups.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the term “porous material” refers to a material which ispermeable such that fluids are movable therethrough by way of pores orother passages. An example of a porous material is a cellulosicmaterial. Other examples of porous materials include stone, concrete,ceramics, and derivatives thereof. As used herein, the term “cellulosicmaterial” refers to a material that includes cellulose as a structuralcomponent. Examples of cellulosic materials include wood, paper,textiles, rope, particleboard and other biologic and syntheticmaterials. As used herein, wood includes solid wood and all woodcomposite materials (e.g., chipboard, engineered wood products, etc.).Cellulosic materials generally have a porous structure that defines aplurality of pores.

As used herein, unless otherwise indicated, the phrase “molecularweight” refers to the nominal molecular weight.

A “treated cellulosic material” is a cellulosic material that has beentreated with a treating agent to modify the properties of the cellulosicmaterial. The properties modified by the treating agent include, but arenot limited to, increased hydrophobicity, dimensional stability, fungiresistance, mold resistance, insect resistance, hardness, surfaceappearance, UV stability, fire resistance, and coatability. Increasingthe hydrophobicity of a cellulosic material can provide other ancillarybenefits, such as dimensional stability, by reducing the rate of wateradsorption and evaporation, thus reducing the internal stresses ofexpanding and contracting.

A “treating agent” is a substance that, when combined with thecellulosic material, modifies the properties of the cellulosic material.In one instance, the treating agent comprises both a polymer and amodifying agent. The treating agent is applied to the cellulosicmaterial. One method of applying the treating agent to the cellulosicmaterial is through impregnation using pressure treatment. In oneinstance, the polymer is applied to the cellulosic material as part of adispersion. Other methods of applying the treating agent are known, suchas brushing, coating, spraying, dipping, soaking and extrusion. Onceapplied, the treating agent will permeate at least a portion of thepores of the cellulosic material.

As used herein, polymer refers to a molecule that is formed from one ormore types of monomers. The polymer is preferably a copolymer or amixture of copolymers and polymers. As used herein, copolymer may referto an alternating copolymer, a periodic copolymer, a statisticalcopolymer, a random copolymer, a block copolymer, a graft copolymer, orother copolymer as is known. As used herein, copolymer refers to apolymer formed by uniting two or more monomers. Examples of copolymersinclude bipolymers, terpolymers, tetrapolymers, and other higher-orderedcopolymers. In one instance, the polymer comprises an olefin-carboxylicacid copolymer. In one instance, the olefin-carboxylic acid copolymercomprises a monomer selected from the group comprising ethylene,propylene, 1-butene, 3-methyl-1-butene, 4-methyl-1-pentene,3-methyl-1-pentene, 1-heptene, 1-hexene, 1-octene, 1-decene, 1-dodecene,butadiene, styrene, (meth)acrylic acid, maleic acid, maleic anhydride,or a mixture thereof. In one instance, a styrene acrylic acid dispersionis suitable, for example, Orotan™ CA-2005, commercially available fromThe Dow Chemical Company. Other suitable polymers and/or copolymerspresent in the mixture include elastomers, plastics and fibers.

In certain embodiments, the polymer comprises a polar olefin polymer,having a polar group as either a comonomer or grafted monomer. As usedherein, a polar olefin polymer is an olefin (co)polymer which containsone or more polar groups. In exemplary embodiments, the polymer may, forexample, comprise one or more polar polyolefins, having a polar group aseither a comonomer or grafted monomer. Examples of polar groups includecarboxylic acids, carboxylic acid anhydrides, carboxylic acid esters,carboxylic acid salts, and carboxylic acid amides. Exemplary polarpolyolefins include, but are not limited to, ethylene/acrylic acid (EAA)and ethylene/methacrylic acid (EMAA) copolymers, such as those availableunder the trademarks PRIMACOR™, commercially available from The DowChemical Company, NUCREL™, commercially available from E.I. DuPont deNemours, and ESCOR™, commercially available from ExxonMobil ChemicalCompany. Exemplary copolymers also include ethylene/maleic anhydridecopolymer, such as those available from The Dow Chemical Company underthe trademark AMPLIFY™ GR. Exemplary copolymers further includeethylene/maleic anhydride and propylene/maleic anhydride copolymers,such as those available from Clariant International Ltd. under thetrademark LICOCENE™. Other exemplary base polymers include, but are notlimited to, ethylene/vinyl acetate copolymer, ethylene/ethyl acrylate(EEA) copolymer, ethylene/methyl methacrylate (EMMA) copolymer, andethylene butyl acrylate (EBA) copolymer.

Other olefin-carboxylic acid copolymers may also be used as the polymer.Copolymers which have ester or anhydride functionalities can beconverted to carboxylic acids or the polymer could also be derived bychemical modification of functional carboxylic acid salts by methodsknown to one skilled in the art. The polymer can also be modified toform other functional groups such as esters or amides and the like.Those having ordinary skill in the art will recognize that a number ofother useful polymers may also be used.

In one embodiment, the base polymer may, for example, comprise a polarpolyolefin selected from the group consisting of ethylene/acrylic acid(EAA) copolymer, ethylene/methacrylic acid copolymer (EMAA), andcombinations thereof. In one instance, the polymer comprisesethylene/(meth)acrylic acid copolymer either alone, or in a mixture withother polymers or copolymers.

As used herein, the use of the term “(meth)” followed by another termsuch as acrylate refers to both acrylates and methacrylates. Forexample, the term “(meth)acrylate” refers to either acrylate ormethacrylate; the term “(meth)acrylic” refers to either acrylic ormethacrylic; and the term “(meth)acrylic acid” refers to either acrylicacid or methacrylic acid.

In one instance, the polymer is a constituent part of an aqueousdispersion. In one instance, the dispersion is a medium that comprisesthe polymer and water. In one instance, the dispersion optionallyincludes one or more organic solvents. The aqueous dispersion isprepared such that the suspended particle size in the dispersion issuitable for penetrating the pores of the cellulosic material fordistribution through the cellulosic material. In one instance, thedispersion also comprises one or more additives. In one instance, anysolids present in the aqueous dispersion are held in a stable suspensionand are transportable by the dispersion into the pores of the cellulosicmaterial. In one instance, the solid content of the dispersion is 1 to75 weight percent. In one instance the organic solvent is an oxygenatedsolvent, a hydrocarbon solvent, a halogenated solvent, or a combinationthereof.

The carboxylic acid portion of the polymer is neutralized with aneutralizing agent at least in part to form a stable aqueous dispersion.As used herein, a neutralizing agent is any material in which thereaction with the carboxylic acid can potentially result in theformation of a salt. In one instance the neutralizing agent is selectedfrom the hydroxides of alkali metals, ammonia or organic derivativesthereof (including amines). In one instance the neutralizing agent is astrong base or a weak base. For example, the neutralizing agent may besodium hydroxide, potassium hydroxide, or ammonia or an amine, such asmonoethanolamine (MEA), triethanolamine (TEA), diethylethanolamine(DEEA) or dimethylaminoethanol (DMEA). AQUACER™ 8804, available from BYKUSA Inc., is an example of a neutralized EAA dispersion. A stabledispersion is a dispersion that is suitable for penetrating the pores ofthe cellulosic material. The neutralizing agent neutralizes at least aportion of the carboxylic acid groups of the polymer. As used herein,neutralization of the carboxylic acid groups refers to any reaction inwhich the hydrogen of the carboxylic acid group is transferred. In oneinstance, 5 to 100 mole percent of the carboxylic acid groups of thepolymer are neutralized by the neutralizing agent. In another instance10 to 80 mole percent of the carboxylic acid groups are neutralized bythe neutralizing agent. In still another instance 20 to 70 mole percentof the carboxylic acid groups are neutralized by the neutralizing agent.

The modifying agent is a substance that, when combined with the polymer,crosslinks at least a portion of the polymer. In one instance, themodifying agent is a diamine, a triamine, a higher-order polyamine or amixture thereof. Suitable modifying agents include polyamines formedfrom the reductive amination of monoethanolamine (ethyleneamines) ormonoisopropanolamine (propyleneamines). Other examples of suitablemodifying agents include triaminononane(4-aminomethyl-1,8-octanediamine), hexamethylenediamine,1,3-diaminopropane, 1,4 diaminobutane, 1,5 diaminopentane,bis(3-aminopropyl)amine, 1,3-pentanediamine,2-methylpentamethylenediamine, bis(hexamethylene)triamine,1,2-diaminocyclohexane, polyethyleneimines, polyallylaminepolyetheramine with multiple amine functionalities (e.g., JEFFAMINE®T-3000), or a mixture thereof. In one instance, the modifying agent isin a solution with a solvent.

The treating agent is combined with the cellulosic material. In oneinstance, the treating agent is introduced to the cellulosic material bypressure treatment, as described herein. In another instance, thetreating agent is introduced to the cellulosic material by othertechniques known in the art, for example, brushing, coating, dipping,soaking, spraying, and extrusion. The treating agent becomes impregnatedin at least a portion of the pores of the cellulosic material, andthereby increases the weight of the cellulosic material. In oneinstance, the polymer increases the weight of the cellulosic material by1 to 80 percent (as calculated after drying the cellulosic material). Inone instance, the treating agent—the combination of the polymer and themodifying agent—increases the weight of the cellulosic material by 5 togreater than 100 percent (as calculated after drying the cellulosicmaterial).

In one instance, the treating agent comprises one or more additives. Theadditive may be included as part of the dispersion, as part of themodifying agent, or may be included separately therefrom. Additiveswhich are known to add properties to treated cellulosic materials aresuitable, such as, flame retardants, dispersants and/or dyes. Forexample, the additives may be organic compounds, metallic compounds, ororganometallic compounds. In one instance, the additive is a materialwhich improves the wetting or penetration of the polymer into the wood,for example, solvents or surfactants (anionic, cationic or nonionic)that are stable in the dispersion. Examples of additives include,solvents, fillers, thickeners, emulsifiers, dispersing agents, buffers,pigments, penetrants, antistatic agents, odor substances, corrosioninhibitors, preservatives, siliconizing agents, rheology modifiers,anti-settling agents, anti-oxidants, other crosslinkers (e.g. diols andpolyols), optical brighteners, waxes, coalescence agents, biocides andanti-foaming agents. Such waxes may include petroleum waxes, paraffinwaxes, a natural wax, or a synthetic wax such as polyethylene wax oroxidized polyethylene wax, beeswax, or slack wax. In addition, thetreating agent may be used in conjunction with wood preservativescontaining, for example, cupric-ammonia, cupric-amine,cupric-ammonia-amine complexes, quaternary ammonium compounds, or othersystems. For example, the treating agent may be used with AlkalineCopper-Quaternary ammonium (ACQ) preservative systems. The treatingagent may also be used with wood preservative technologies which usezinc salts or boron containing compounds. Optionally, other additivessuch as insecticides, termiticides, fungicides, and moldicides may beadded to the treating agent. In one instance, the additive is includedas part of the dispersion and forms a stable suspension therewith. Inone instance, one or more surfactant is added to the dispersion. In oneinstance, a surfactant is selected which reduces gelling of the polymerat the surface of the cellulosic material. In one instance, a surfactantis selected which increases the amount of polymer impregnated in thecellulosic material. For example, suitable surfactants may be nonionic,anionic, or cationic. Examples of nonionic surfactants include:alkoxylated alcohols, alkoxylated alkyl phenols, fatty acid esters,amine and amide derivatives, alkylpolyglucosides, ethyleneoxide/propylene oxide copolymers, polyols and alkoxylated polyols. Forexample, a nonionic surfactant is TERGITOL™ L-62, commercially availablefrom The Dow Chemical Company. Examples of anionic surfactants include:alkyl sulfates, alkyether sulfates, sulfated alkanolamides, alpha olefinsulfonates, lignosulfonates, sulfosuccinates, fatty acid salts, andphosphate esters. For example, an anionic surfactant is DOWFAX™ C10L,commercially available from the Dow Chemical Company. Examples ofcationic surfactants include alkyltrimethylammonium salts.

In one instance, the cellulosic material is prepared as a treatedcellulosic material by pressure treatment. The pressure used to pressuretreat the cellulosic material may be either higher or lower thanatmospheric pressure. In one instance, the pressure is lower thanambient pressure, for example, 0.0001 to 0.09 MPa (0.75 to 675 mmHg). Inanother instance, the pressure is greater than ambient pressure, forexample, 0.1 to 1.7 MPa (750 to 12750 mmHg). It is envisioned thatpressure treatment processes known in the art are suitable forimpregnating the cellulosic material with the treating agent.

In one instance, the treated cellulosic material is prepared accordingto at least a first treatment protocol and a second treatment protocol.In one instance, the first treatment protocol comprises impregnating thecellulosic material with the polymer. The first treatment protocolcomprises one or more of the following steps: (a) depositing thecellulosic material in a vessel; (b) holding the vessel at vacuum for 5to 60 minutes; (c) introducing the polymer to the vessel; (d)pressurizing the vessel to 1.03 MPa for 5 to 60 minutes; (e) drainingthe excess polymer; (f) optionally removing excess polymer by vacuum;and (g) air drying the cellulosic material at 20 to 60° C. for 24 to 48hours. In one instance, the polymer is part of the aqueous dispersion.

In one instance, the product of the first treatment protocol issubsequently prepared according to a second treatment protocol thatimpregnates the cellulosic material with the modifying agent. The secondtreatment protocol comprises one or more of the following steps: (a)depositing the cellulosic material prepared according to the firsttreatment protocol in a vessel; (b) introducing the modifying agent tothe vessel; (c) holding the vessel at either vacuum or increasedpressure for 5 to 60 minutes; (d) optionally removing excess modifyingagent by vacuum; and (e) air drying the cellulosic material at 60° C.for 24 to 48 hours.

In one instance, the product of the second treatment protocol issubsequently neutralized according to a neutralization protocol thatneutralizes any residual modifying agent from the second treatmentprotocol by the use of a modifying agent neutralizer. In one instance,the modifying agent neutralizer is any material suitable for reactingwith the modifying agent to reduce its basicity, for example, thedispersion. The neutralization protocol comprises one or more of thefollowing steps: (a) depositing the cellulosic material preparedaccording to the second treatment protocol in a vessel; (b) introducingthe modifying agent neutralizer to the vessel for 30 minutes; and (c)air drying the cellulosic material at 60° C. for 24 to 48 hours.

The several drying steps may be performed at a range of temperatures,whereby the duration of the air drying step is proportional to thetemperature. Suitable air-drying temperatures are between roomtemperature (roughly 20° C.) and 180° C. The drying may be performed inair, in nitrogen, or other suitable atmosphere.

A water immersion test is used to determine the water repellency of thetreated cellulosic material according to the American Wood ProtectionAssociation Standard E4-11 procedure (Standard Method of Testing WaterRepellency of Pressure Treated Wood). The water immersion test involvesfirst, providing both a treated wafer, comprising a treated cellulosicmaterial prepared as described herein, and a control wafer, comprising acellulosic material treated according to the first treatment protocoldescribed herein except that the dispersion is replaced by distilledwater; second, measuring the tangential dimension of both the treatedwafer and the control wafer to provide an initial tangential dimension(T₁) (where the tangential dimension is perpendicular to the directionof the grain of the cellulosic material); third, placing both thetreated wafer and the control wafer in a conditioning chamber maintainedat 65±3% relative humidity and 21±3° C. until a constant weight isachieved; fourth, immersing both the treated wafer and the control waferin distilled water at 24±3° C. for 30 minutes; and fourth, measuring thetangential dimension of both the treated wafer and the control waferfollowing removal from the water to provide a post tangential dimension(T₂).

DoN refers to the degree of neutralization of the carboxylic acidfunctionality in the polymer.

The percent swelling (S) for each individual wafer (both the treatedwafer and the control wafer) is calculated as:

${S\mspace{14mu} (\%)} = {\frac{T_{2} - T_{1}}{T_{1}} \times 100}$

In each of the Examples herein, the percent swelling of the controlwafer is 4.7%.

Water-repellency efficiency (WRE) is used to determine the effectivenessof the treating agent in adding water repellant properties to thetreated cellulosic material. WRE is calculated as:

${W\; R\; E\mspace{14mu} (\%)} = {\frac{S_{1} - S_{2}}{S_{1}} \times 100}$

S₁ refers to the percent swelling of the untreated wafer; S₂ refers tothe percent swelling of the treated wafer. According to E4-11, for mostoutdoor applications a minimum WRE of 75% is preferred. The WRE of rawwood without any treatment is 0%.

The hardness of the treated cellulosic material is determined accordingto the Shore (Durometer) test using a Type D Durometer (30° cone, 1.40mm diameter, 2.54 mm extension, 44.48N spring force). Hardness isdetermined using the Type D Durometer by placing the cellulosic materialon a hard flat surface, and the foot of the durometer is pressed withthe given spring force against the cellulosic material. The hardnessvalue is recorded from the gauge on the Durometer within one second ofcontact with the cellulosic material. At least five hardness tests wereperformed per sample of cellulosic material. Hardness values reportedherein are averages of the tests performed for a given cellulosicmaterial. The hardness value of an untreated wafer is 40.

The following Examples illustrate certain aspects of the presentdisclosure, but the scope of the present disclosure is not limited tothe following Examples.

The dispersions in the following Examples were made by combining thepolymer with the given amount of base in a mixed, pressurized vessel at120° C. as is known in the art (for example, a suitable dispersion maybe prepared according to “Preparation of Aqueous Dispersions of PRIMACORCopolymers” from The Dow Chemical Company). All the vacuum operations inthe examples are in the range of −0.00399 MPa to −0.00267 MPa.

Example 1

A pine wafer (southern yellow pine, 4 cm×2 cm×0.5 cm) is held at thebottom of a Parr reactor by a weight (here a ring is used). The reactorpressure is set to vacuum for 30 minutes. 80 ml of a dispersioncomprising 38 percent by weight Primacor 5980i (35% DoN with NH₃, 8.35pH, particle size of 113 nm, 38% solid concentration) and 62 percent byweight water is introduced to the reactor. The reactor pressure is thenset to 1.03 MPa for 60 minutes under nitrogen. The wafer is then placedin an oven and air dried at 60° C. for 48 hours. The wafer is held atthe bottom of the reactor by the weight. The reactor is filled withsufficient ethylenediamine (EDA) to submerge the wafer. The reactorpressure is set to vacuum for 60 minutes. The wafer is then placed in anoven and air dried at 60° C. for 48 hours. The treated wafer and thecontrol wafer are each processed according to the E4-11 procedure. Thepercent swelling for the treated wafer is 1.4%; the WRE of the treatedwafer is 70.9%. The hardness of the treated wafer is measured as 49.0using a Type D Durometer.

Example 2

A pine wafer (southern yellow pine, 4 cm×2 cm×0.5 cm) is held at thebottom of a Parr reactor by a weight (here a ring was used). The reactorpressure is set to vacuum for 30 minutes. 80 ml of a dispersioncomprising 20 percent by weight Primacor 5980i dispersion (50% DoN withMEA, 20% solid concentration, 8.21 pH, particle size of 117 nm) and 80percent by weight water is introduced to the reactor. The reactorpressure is then set to 1.03 MPa for 60 minutes under nitrogen. Thewafer is then placed in an oven and air dried at 60° C. for 48 hours.The wafer is held at the bottom of the reactor by the weight. Thereactor is filled with sufficient triaminononane (TAN) to submerge thewafer. The reactor pressure is set to vacuum for 60 minutes. The waferis then placed in an oven and air dried at 60° C. for 48 hours. Adiluted polyolefin dispersion (5% solid concentration) is prepared byadding 76 ml of water to 10 ml of the dispersion. The wafer is thenplaced in the diluted polyolefin dispersion for 30 minutes and is thenplaced in an oven and air dried at 60° C. for 48 hours, therebyproviding a treated wafer. The treated wafer and the control wafer areeach processed according to the E4-11 procedure. The percent swellingfor the treated wafer is 0.038%; the WRE of the treated wafer is 98.95%.The hardness of the treated wafer is measured as 60 using a Type DDurometer.

Example 3

A pine wafer (southern yellow pine, 4 cm×2 cm×0.5 cm) is held at thebottom of a Parr reactor by a weight (here a ring was used). The reactorpressure is set to vacuum for 30 minutes. 80 ml of a dispersioncomprising 10 percent by weight Primacor 5990i (60% DoN with MEA), 6 wt% TERGITOL™ L-62, and 84% water is introduced to the reactor. TERGITOL™L-62 is a nonionic surfactant manufactured by The Dow Chemical Company.The reactor pressure is then set to 1.03 MPa for 60 minutes undernitrogen. The wafer is then placed in an oven and air dried at 60° C.for 48 hours, thereby providing a treated wafer. The weight gain of thewood after treatment is 30%. The treated wafer and the control wafer areeach processed according to the E4-11 procedure. The percent swellingfor the treated wafer is 4.5%; the WRE of the treated wafer is 3.5%. Thehardness of the treated wafer is measured as 45.2 using a Type DDurometer.

Example 4

A pine wafer (southern yellow pine, 4 cm×2 cm×0.5 cm) is held at thebottom of a Parr reactor by a weight (here a ring was used). The reactorpressure is set to vacuum for 30 minutes. 80 ml of a dispersioncomprising 10 percent by weight Primacor 5990i (60% DoN with MEA,) and90 percent by weight water is introduced to the reactor. The reactorpressure is then set to 1.03 MPa for 60 minutes under nitrogen. Thewafer is then placed in an oven and air dried at 60° C. for 48 hours,thereby providing a treated wafer. The weight gain of the wood aftertreatment is 19%. The treated wafer and the control wafer are eachprocessed according to the E4-11 procedure. The percent swelling for thetreated wafer is 4.2%; the WRE of the treated wafer is 10.1%. Thehardness of the treated wafer is measured as 45.0 using a Type DDurometer.

Example 5

A pine wafer (southern yellow pine, 4 cm×2 cm×0.5 cm) is held at thebottom of a Parr reactor by a weight (here a ring is used). The reactorpressure is set to vacuum for 30 minutes. 80 ml of a dispersioncomprising 94 percent by weight PRIMACOR™5980i aqueous dispersion (60%DoN with TEA, 7.8 pH, particle size of 18.5 nm, 24% solid concentration)and 6 percent by weight DOWFAX™ C10L is introduced to the reactor. Thereactor pressure is then set to 1.03 MPa for 60 minutes under nitrogen.The wafer is then placed in an oven and air dried at 60° C. for 48hours. The wafer is held at the bottom of the reactor by the weight. Thereactor is filled with sufficient 10 wt % JEFFAMINE® T-3000 aqueoussolution to submerge the wafer. The JEFFAMINE®T-3000 polyetheraminepurchased from Huntsman Company is a triamine of approximately 3000molecular weight. The reactor pressure is set to 150 psi for 60 minutes.The wafer is then placed in an oven and air dried at 60° C. for 48hours, thereby providing a treated wafer. The treated wafer and acontrol wafer are each processed according to the E4-11 procedure. Thepercent swelling for the first piece of the wafer is 1.2%; the WRE ofthe first piece of the wafer is 74.3%. The hardness of the treated waferis measured as 50.8 using a Type D Durometer.

Example 6

A pine wafer (southern yellow pine, 4 cm×2 cm×0.5 cm) is held at thebottom of a Parr reactor by a weight (here a ring is used). The reactorpressure is set to vacuum for 30 minutes. 80 ml of a dispersioncomprising 94 percent by weight PRIMACOR™5980i aqueous dispersion (60%DoN with TEA, 7.8 pH, particle size of 18.5 nm, 24% solid concentration)and 6 percent by weight DOWFAX™ C10L is introduced to the reactor. Thereactor pressure is then set to 1.03 MPa for 60 minutes under nitrogen.The wafer is then placed in an oven and air dried at 60° C. for 48hours. The wafer is held at the bottom of the reactor by the weight. Thereactor is filled with sufficient 5 wt % JEFFAMINE®T-3000 aqueoussolution to submerge the wafer. The JEFFAMINE®T-3000 polyetheraminepurchased from Huntsman Company is a triamine of approximately 3000molecular weight The reactor pressure is set to 150 psi for 60 minutes.The wafer is then placed in an oven and air dried at 60° C. for 48hours, thereby providing a treated wafer. The treated wafer and acontrol wafer are each processed according to the E4-11 procedure. Thepercent swelling for the first piece of the wafer is 1.7%; the WRE ofthe first piece of the wafer is 61.9%. The hardness of the treated waferis measured as 50.2 using a Type D Durometer.

Example 7

A pine wafer (southern yellow pine, 4 cm×2 cm×0.5 cm) is held at thebottom of a Parr reactor by a weight (here a ring is used). The reactorpressure is set to vacuum for 30 minutes. 80 ml of a dispersioncomprising 94 percent by weight PRIMACOR™5980i aqueous dispersion (60%DoN with TEA, 7.8 pH, particle size of 18.5 nm, 24% solid concentration)and 6 percent by weight DOWFAX™C10L is introduced to the reactor. Thereactor pressure is then set to 1.03 MPa for 60 minutes under nitrogen.The wafer is then placed in an oven and air dried at 60° C. for 48hours. The wafer is held at the bottom of the reactor by the weight. Thereactor is filled with sufficient 5 wt % polyallylamine aqueous solutionto submerge the wafer. The reactor pressure is set to 150 psi for 60minutes. The wafer is then placed in an oven and air dried at 60° C. for48 hours, thereby providing a treated wafer. The treated wafer and acontrol wafer are each processed according to the E4-11 procedure. Thepercent swelling for the first piece of the wafer is 0.45%; the WRE ofthe first piece of the wafer is 90.3%. The hardness of the treated waferis measured as 52.8 using a Type D Durometer.

Example 8

A pine wafer (southern yellow pine, 4 cm×2 cm×0.5 cm) is held at thebottom of a Parr reactor by a weight (here a ring is used). The reactorpressure is set to vacuum for 30 minutes. 80 ml of a dispersioncomprising 94 percent by weight PRIMACOR™5980i aqueous dispersion (60%DoN with TEA, 7.8 pH, particle size of 18.5 nm, 24% solid concentration)and 6 percent by weight DOWFAX™ C10L is introduced to the reactor. Thereactor pressure is then set to 1.03 MPa for 60 minutes under nitrogen.The wafer is then placed in an oven and air dried at 60° C. for 48hours. The wafer is held at the bottom of the reactor by the weight. Thereactor is filled with sufficient 5 wt % polyethyleneimine withmolecular weight of 75,000 Da aqueous solution to submerge the wafer.The reactor pressure is set to 150 psi for 60 minutes. The wafer is thenplaced in an oven and air dried at 60° C. for 48 hours, therebyproviding a treated wafer. The treated wafer and a control wafer areeach processed according to the E4-11 procedure. The percent swellingfor the first piece of the wafer is 1.4%; the WRE of the first piece ofthe wafer is 70.1%. The hardness of the treated wafer is measured as48.8 using a Type D Durometer.

Example 9

A pine wafer (southern yellow pine, 4 cm×2 cm×0.5 cm) is held at thebottom of a Parr reactor by a weight (here a ring is used). The reactorpressure is set to vacuum for 30 minutes. 80 ml of a dispersioncomprising 94 percent by weight PRIMACOR™5980i aqueous dispersion (60%DoN with TEA, 7.8 pH, particle size of 18.5 nm, 24% solid concentration)and 6 percent by weight DOWFAX™ C10L is introduced to the reactor. Thereactor pressure is then set to 1.03 MPa for 60 minutes under nitrogen.The wafer is then placed in an oven and air dried at 60° C. for 48hours. The wafer is held at the bottom of the reactor by the weight. Thereactor is filled with sufficient 10 wt % polyethyleneimine (molecularweight of 75,000 Da) aqueous solution to submerge the wafer. The reactorpressure is set to 150 psi for 60 minutes. The wafer is then placed inan oven and air dried at 60° C. for 48 hours, thereby providing atreated wafer. The treated wafer and a control wafer are each processedaccording to the E4-11 procedure. The percent swelling for the firstpiece of the wafer is 0.86%; the WRE of the first piece of the wafer is81.7%. The hardness of the treated wafer is measured as 47.5 using aType D Durometer.

The Examples illustrate that when the cellulosic material contains thetreating agent, including both the polymer and the modifying agent,favorable WRE results are obtained. However, where the cellulosicmaterial has not been treated by both the polymer and the modifyingagent, such as in Comparative Examples 3 and 4, favorable WRE resultsare not obtained.

1. A treated cellulosic material comprising: a cellulosic materialhaving a porous structure defining a plurality of pores, the cellulosicmaterial comprising wood including wood or wood composite materials, atleast a portion of the pores containing a treating agent comprising: apolymer comprising an olefin-carboxylic acid copolymer; and a modifyingagent comprising a polyamine having greater than or equal to 2 aminegroups, wherein the modifying agent crosslinks at least a portion of thepolymer.
 2. The treated cellulosic material of claim 1, wherein at leasta portion of the carboxylic acid groups of the copolymer areneutralized.
 3. The treated cellulosic material of claim 1, wherein theolefin-carboxylic acid copolymer comprises, in polymerized form, amonomer selected from the group comprising ethylene, propylene,1-butene, 3-methyl-1-butene, 4-methyl-1-pentene, 3-methyl-1-pentene,1-heptene, 1-hexene, 1-octene, 1-decene, 1-dodecene, butadiene, styreneor a mixture thereof.
 4. The treated cellulosic material of claim 1,wherein the olefin-carboxylic acid copolymer comprises, in polymerizedform, a carboxylic acid monomer or anhydride monomer selected from thegroup comprising (meth)acrylic acid, maleic acid, maleic anhydride or amixture thereof.
 5. The treated cellulosic material of claim 1, whereinthe polymer comprises one or more polymers in addition to theolefin-carboxylic acid copolymer.
 6. The treated cellulosic material ofclaim 1, wherein the modifying agent comprises a diamine, a triamine, ahigher-order polyamine or a mixture thereof.
 7. The treated cellulosicmaterial of claim 1, wherein the modifying agent comprisesethylenediamine, triaminononane, ethyleneamines, propyleneamines,hexamethylenediamine, 1,3-diaminopropane, 1,4 diaminobutane, 1,5diaminopentane, bis(3-aminopropyl)amine, 1,3-pentanediamine,2-methylpentamethylenediamine, bis(hexamethylene)triamine,1,2-diaminocyclohexane or a mixture thereof.
 8. The treated cellulosicmaterial of claim 1, wherein the polymer is ethylene-acrylic acidcopolymer.
 9. The treated cellulosic material of claim 1, wherein thetreated cellulosic material is prepared by (1) impregnating thecellulosic material with an aqueous dispersion comprising the polymerand (2) impregnating the cellulosic material with the modifying agent.10. The treated cellulosic material of claim 1, wherein the treatingagent further comprises one or more additives.
 11. A method forpreparing a treated cellulosic material comprising: (a) providing acellulosic material; (b) a first treatment protocol comprisingimpregnating the cellulosic material with an aqueous dispersioncomprising a polymer, the polymer comprising an olefin-carboxylic acidcopolymer; and (c) a second treatment protocol comprising impregnatingthe cellulosic material with a modifying agent, the modifying agentcomprising a polyamine having greater than or equal to 2 amine groups.12. The method of claim 11, wherein the impregnating of the firsttreatment protocol is conducted under pressure greater than or lowerthan ambient.
 13. The method of claim 11, wherein the modifying agentcomprises ethylenediamine, triaminononane, ethyleneamines,propyleneamines, hexamethylenediamine, 1,3-diaminopropane, 1,4diaminobutane, 1,5 diaminopentane, bis(3-aminopropyl)amine,1,3-pentanediamine, 2-methylpentamethylenediamine,bis(hexamethylene)triamine, 1,2-diaminocyclohexane or a mixture thereof.14. The method of claim 11, wherein the method further comprises: (d) aneutralization protocol comprising impregnating the cellulosic materialwith the aqueous dispersion.